1. Technical Field
Embodiments of the present disclosure are directed to a backlight unit that can reduce chromatic deviation of light directed by a light guide plate.
2. Discussion of the Related Art
Light emitting diodes (LEDs), which can be characterized by low power consumption and high efficiency, have been recently widely used as a light source of a backlight unit. The LEDs may be provided in a package form within a backlight unit. In this case, one package may include an LED chip and a fluorescent member, such as a phosphor, surrounding the LED chip. An LED chip generally emits blue light and the blue light may pass through the phosphor to be converted into white light.
In addition, in a structure where a lateral surface of an LED chip is positioned opposite to a light guide plate, light emitted toward the lateral surface of the LED chip may have a light path that is relatively longer than that of light emitted toward a front surface thereof, such that light emitted toward the lateral surface may mostly concentrate on end portions of the light guide plate. In other words, the light emitted toward the lateral surface may be concentrated on a light emitting surface of the light guide plate disposed far from an incident surface thereof.
Light emitted toward the lateral surface of the LED chip may appear yellowish compared to light emitted toward the front surface of the LED chip. That is because a proportion of white light to the light emitted toward the lateral surface of the LED chip is relatively low. Accordingly, light emitted toward the lateral surface of the LED chip may appear yellowish compared to the light emitted toward the front surface.
Therefore, in a conventional backlight unit, yellowish light may be relatively concentrated in a part of a light emitting surface of a light guide plate disposed far from a light incident surface, so that some level of yellowish color may appear in a corresponding area of a displayed image as compared other areas of the displayed image.